There are many difficulties inherent in the preparation of frozen desserts which are made by a process employing static freezing. Static freezing refers to the process step of freezing without concurrent agitation or aeration. Generally, frozen desserts made by static freezing do not compare in consistency and overall appearance to conventional frozen desserts made by the normal commercial process which involves agitation during the freezing process. Ordinarily, if frozen desserts formlations are not agitated during freezing large ice crystals are formed. Also, the fat base will tend to separate from the other components of the mix yielding a non-homogeneous product. Such results adversely affect texture, dryness, uniformity of appearance of the frozen dessert thereby affecting the overall quality of the product.
The normal commercial process for preparing frozen desserts involves mixing, pasteurizing and homogenizing the ingredients to form an emulsion which is then cooled with agitation with concurrent aeration and solidification to form a frozen dessert. The frozen dessert may be held at a lower temperature to "harden" the product and is then maintained at a temperature below about 30.degree.F in order to maintain its hard consistency. Failure to maintain the dessert at relatively low temperature results in the development of large crystals of the sugar lactose and/or of ice which degrade the quality of the product.
It is apparent that it would be highly desirable to be able to make a frozen dessert product having good qualities from a shelf-stable mix by simply whipping conveniently available ingredients in a home mixer and then static freezing the aerated mixture in the freezing compartment of a home refrigerator or freezer without agitation. It would be even more desirable if such a product could be thawed or melted and then, without aeration, refrozen to provide a frozen dessert still having the good consistency, texture, flavor and overall appearance the product had before melting. This quality of retaining product characteristics during temperature cycling is referred to as freeze-thaw stability.
While much product development work has been conducted in the frozen dessert field, there remains a need for a high quality frozen dessert which can be conveniently prepared by the consumer with a minimum amount of equipment, effort, and expertise concerning methods for preparing frozen desserts. The prior art teaches compositions and processes for making frozen dessert products both with and without agitation during freezing and products which can be made by relatively simple process steps. Examples of prior art in this field include: U.S. Pat. No. 3,800,036, Mar. 26, 1974, to Gabby et al. and U.S. Pat. No. 3,183,098, May 11, 1965, to Baur.
It is well known in the art that each ingredient of a frozen dessert composition affects and contributes to the overall quality of the frozen dessert and that frozen dessert processing can be quite complex. Although each ingredient has a separate function, each also interacts with each other ingredient to form a final product with characteristics that would have been difficult or impossible to predict from the known properties of each individual ingredient. Thus, one of the objects of the present invention is to provide a novel combination of ingredients which, when combined, agitated and then frozen interact with each other to provide a tasteful, highly aerated frozen dessert having good appearance, dryness, body, flavor and eating qualities.
Another object of the present invention is to provide a frozen dessert having good qualities which are retained even when the dessert is thawed and then re-frozen without agitation. That is, it is an object of this invention to provide a product having freeze-thaw stability.
It is a further object of this invention to provide a frozen dessert which can be made by convenient process which does not require agitation during the freezing step. That is, it is an object of this invention to provide a frozen dessert which can be made by static freezing.
It is yet another object of this invention to provide a frozen dessert which can be conveniently prepared in the home. More specifically, it is an object of this invention to provide a frozen dessert which can be prepared in the home without employing a heating step, or unusual or expensive utensels or equipment or an extended whipping time.
Still another object of this invention is to provide a frozen dessert made from mix ingredients which are shelf stable with respect to functional and microbiological deterioration.
These and still other objects will be apparent from the following description of the present invention.